This project is an exogenously-collateralized cross-chain stablecoin, built from a token contract that is controlled by an "engine" contract. The engine contract utilizes API3 for pricefeed data and Wormhole for cross chain functionality.
This project consists of two contracts deployed across two chains. The first is the CrossChainStableCoin.sol contract, which is the CCSC token contract for minting and burning. The second is the CCSCEngine.sol contract, which the CCSC token contract through Wormhole. The engine contract uses API3's pricefeed data to secure the algorithmically generated stablecoin. The token contract is deployed on Avalanche Fuji and the engine contract is deployed on Ethereum Goerli.
The Cross Chain Stable Coin keeps its stable price by allowing users to mint an appropriate amount equivalent to their deposit based on API3 oracle prices, and allowing other users to liquidate positions if collateral prices drop too low.
The Cross Chain Stable Coin is exogenously-collateralized because the token used for collateral is not native to the CCSC system and can be from anywhere.
The CrossChainStableCoin.sol contract has a mint() and a burn() function. These functions can only be called by the WormholeRelayer when a message is received from the Engine contract with instructions to mint or burn, a certain amount and the recipient of the action.
The CCSCEngine.sol contract mints CCSC tokens in exchange for over-collateralized deposits. The CCSC address and collateral get set in the constructor. The CCSCEngine takes in an array of pricefeed addresses that correspond to an array of collateral token addresses. The value of the deposited collateral must be more than the CCSC that is minted in exchange. If the value of the collateral declines based on price data from API3, other users may liquidate() a collateralized position to maintain the CCSC token's stable value.
The HelperConfig script dictates the constructor arguments based on the network being deployed to. The collateral tokens have been set to WETH and WBTC so the pricefeeds we are using are API3's ETH/USD and BTC/USD feeds.
To install the necessary dependencies, first ensure that you have Foundry installed by running the following command:
curl -L https://foundry.paradigm.xyz | bash
Then run the following commands in the project's root directory:
foundryup
forge install
You will need to have a .env file in each directory with your $PRIVATE_KEY.
Replace $PRIVATE_KEY, $GOERLI_RPC_URL and $FUJI_RPC_URL in the .env with your respective private key and rpc url.
Deploy the CrossChainStableCoin.sol and CCSCEngine.sol contracts to their chains by running the following commands:
source .env
forge script script/DeployCrossChainStableCoin.s.sol --private-key $PRIVATE_KEY --rpc-url $FUJI_RPC_URL --broadcast
forge script script/CCSCEngine.s.sol --private-key $PRIVATE_KEY --rpc-url $GOERLI_RPC_URL --broadcast
The setWormholeRelayer() will have to be called on both contracts with their respective relayer addresses found in the Wormhole docs.
This project is licensed under the MIT License.